FIELD OF THE INVENTION
The present invention relates to a device for controlling access to a space closed by a door, such as a motor vehicle cabin for example and, more specifically, to such a device comprising electronic means for interrogating an emitter/receiver circuit worn or carried by a person wishing to open said door, to recognize a predetermined code emitted in response by said circuit and to then cause a locking pin to be withdrawn from a notch in a bolt that forms part of the door lock, and means by which said person can activate said electronic means.
Depicted diagrammatically in FIG. 1 of the appended drawing is a known device, for controlling access to a motor vehicle, which works by the recognition of a code emitted by a badge 1 worn by a person wishing to enter the vehicle. The badge 1 has an electronic circuit for emitting this code, but this emission is not permanent, in order to save the electric battery that powers the circuit. The circuit is activated on reception of a signal emitted by the antenna 2 of electronic means 3 comprising a computer, which means are placed in the vehicle and are capable of recognizing the code emitted in return by the badge 1 so as to allow or deny the person in question access to the vehicle. These electronic means 3 are themselves activated by this person, by pressing the button of a switch 4 placed on the door 5 of the vehicle, near to a handle such as a lever handle 6 for opening this door, this handle being articulated to this door at 6.
This button has the drawback of being visible and it may therefore be desirable to conceal it within the bodywork, it then being actuated via the lever handle 6. This handle makes it possible, via a linkage 7 depicted very diagrammatically in the figure, to withdraw a bolt 8 from a keeper 9 to allow the door 5 to be opened, as long as a pin 10 that immobilizes the bolt 8 is disengaged from a notch 11 formed in this bolt. Obviously, it is the electronic means 3 which cause this disengagement, with the aid of an electromagnet 12, for example, when the code emitted by the badge is such that the person wearing this badge is authorized to enter the vehicle.
The following difficulty is encountered when provision is made for the actuation of the switch 4 to be mechanically coupled to the actuation of the lever handle 6 for opening the door: a pulling action exerted on the lever handle 6 by a person who wants to get into the vehicle has the effect of bringing the pin 10 into abutment against a flank of the notch 11, creating substantial friction between these two parts. If then the means 3, having recognized and accepted the code emitted by the badge 1, energize the electromagnet 12 to disengage the pin 10 from the bolt 8 and thus allow the door 5 to be opened, this friction may prevent the disengagement of the pin and the door then remains closed. In order to overcome this, the person may then release his pulling action on the lever handle 6 so as to reduce the bolt/pin friction and allow these two components to disengage. This additional maneuver is, however, an irksome task which it is desirable to eliminate.